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U.S. Department of Transportation U.S. Department of Transportation Icon United States Department of Transportation United States Department of Transportation

Safety concerns involving Model B1 relays, manufactured by General Railway Signal (GRS), between the years 1960 and 1985, and their potential to stick and remain in the energized position. ALSTOM Signaling,Inc., which has acquired GRS, estimates that app

Document Series
Safety Advisories
Safety Advisory Number
Subject Signal and Train Control
Signal and Train Control; GRS ;� relay failure; B1 relay
sa2000_1.pdf (9.56 KB)

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Effective Date: Thursday, May 11, 2000